Page 101 - Basics of MATLAB and Beyond
P. 101

>> meteo(2).Pressure(2:3) = [NaN NaN];
                               >> meteo(2).Pressure
                               ans  =
                                       1015          NaN          NaN

                               Suppose now that we have discovered that all our pressure readings were
                               wrong; we need to delete the pressure field altogether from the structure:


                               >> meteo = rmfield(meteo,’Pressure’)
                               meteo =
                               1x2 struct array with fields:
                                   Site
                                   Time
                                   Temperature
                               Now we want to add humidity measurements at the two sites. Suppose
                               Adelaide’s humidity was 69% and Sydney’s was 86%, 80%, and 76% at
                               the three different times:

                               [meteo.humidity] = deal(69,[86 80 76]);
                               >> meteo(1)
                               ans =
                                          Site: ’Adelaide’
                                          Time: 2.3000
                                   Temperature: 24
                                      humidity: 69
                               >> meteo(2)
                               ans =
                                          Site: ’Sydney’
                                          Time: [4 8 11]
                                   Temperature: [19 16.5000 15.3000]
                                      humidity: [86 80 76]
                               (The deal command copies a list of inputs to a list of outputs.)
                                  To do operations on field elements, just treat them as any other
                               matlab array:

                               >> meteo(2).Temperature
                               ans  =
                                  19.0000    16.5000   15.3000
                               >> mean(meteo(2).Temperature)
                               ans  =
                                  16.9333
                               The temperature measurements at both sites in the structure are
                               accessed by typing:




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